30 June 2020

The 18 June 2020 Achoma landslide in Peru

Posted by Dave Petley

The 18 June 2020 Achoma Landslide in Peru

On 18 June 2020 the very large Achoma Landslide occurred in valley of the Rio Colca in Peru.  Many thanks to Gael Araujo of the Geological Service of Peru for highlighting this one to me, and to Robert Simmon of Planet Labs who independently identified it from satellite imagery.  As far as I am aware, this landslide has not been reported in the English language media, but it is a very large, valley-blocking failure. La Republica has some drone imagery that gives a good impression of the scale of the landslide:-

Achoma landslide

Drone imagery of the the 18 June 2020 Achoma landslide in Peru. Image by Ingemmet via La Republica.


As the image shows, the landslide has blocked the Rio Colca, allowing a lake to form.  As of yesterday, the volume of the lake was about 2 million cubic metres. A state of emergency has been declared for the area, lasting 60 days, whilst efforts are being undertaken to drain the lake.  The video below, collected by Ingemmet, should provide a good impression of the scale of this landslide:-



As noted above, Planet Labs has collected an excellent satellite image of this landslide:-


This image clearly captures the scale of both the landslide (which covers an area of about 40 hectares) and the developing barrier lake.


On reflection 1: A rare peat bog landslide in Eire

It appears that a large peat bog landslide occurred in North Leitrim in Eire over the weekend, triggered by heavy rainfall.  Does anyone have any more information?


On reflection 2: The Tylerstown landslide – an update

Work has started to clear the 60,000 tonnes of landslide debris from the Tylorstown landslide in Wales.